The short answer
Villas in the Italianate style usually have a low-pitched hipped roof, wide eaves on brackets, and a covering of slate with lead in the hips and valleys. Because the pitch is shallow, the slate's laps, fixings and lead details do the work that a steep slope does elsewhere.
Kingshill House, built in the mid-1800s, gives the hill its best-known example of the style. The same features turn up on smaller villas and large houses nearby, so what follows applies well beyond the one listed building.
Q1.1How shallow can a slate roof go?
Natural slate needs a minimum pitch of 20 degrees under BS 5534, as Cupa Pizarras sets out for a moderate-exposure roof with 500 mm slates, and hook fixings should not be used below 25 degrees. Low-pitched villa roofs sit close to those limits, so the headlap, the overlap of each slate by the one two courses above, matters more than usual. A slate that has slipped by a few millimetres can let water behind it. On a roof of this type we check the nail or clip on every slipped slate before refixing it, because a slate that slid once will slide again if the cause is not cured.
Q1.2Why do the hips and valleys need lead?
A hipped roof slopes on every side, so it has hips instead of gables. Each hip needs a covering of ridge or lead, and every internal corner needs a valley gutter. These lead details outlive the slates around them if they are sound, but they split along folds and at their fixings. A tired valley is a frequent cause of a stain on a ceiling under the roof.
Q1.3What about the deep eaves and brackets?
Deep eaves shed water clear of the wall, but the timber soffit and brackets are exposed to the weather. Rot there is a repair job for a carpenter as much as a roofer, and the two need to agree the sequence so that the new boards are not soaked before the roof is sealed, and our slate roofing page covers how the two trades fit together.
Chimneys on a villa are generally tall and plain, with a stack on each party wall or gable. Pointing, flaunching and the lead tray at the base all need checking on the same visit as the hips, and a cracked pot or a loose cowl is a quick fix while the access is in place.